Prescribed Burning in Longleaf Forests
In this video Ike McWhorter, Fire Ecologist for the US Forest Service discusses a recent burn and the benefits to the forest ecosystem.
Prescribed Burning in Longleaf Forests Audio Transcription
Prescribed Burn Audio File Transcription
This is a 10-12 year old Longleaf Plantation that was recently burned. The landowner wanted to get fire back in here to try and open up the stand, to get rid of some of the encroaching hardwoods and Loblolly and Shortleaf Pines and to stimulate the ground cover. It’s pretty dense so he was very cautious about the kind of fire he has got in here, he didn’t want it to get too hot but he wanted it hot enough to do some good in controlling some of these other species. From the outside it is hard to tell really what the fire did, we see some brown needles, and brown leaves, but a lot of green on the tree. We have to go inside the stand to really see what the fire effects were.
One of the concerns of the landowner was the amount of fuel that was in his stand, he was concerned that the fire would be too hot and would kill his residual stand of Longleaf but he still wanted the fire to be hot enough to kill the young Loblollys and Shortleaf Pines that were coming in as well as the Yaupon. The idea was to open the stand up and allow light in and to stimulate the ground cover. Now you see a lot of dead or browned out needles and leaves on the trees, this is from the scorch from the heat of the fire that browned these out. They will eventually fall and add to more fuel on the ground. If we look on the ground we can see this nice layer of new needles that have fallen since the fire. Underneath you can see the ones that burned or the chard needles that remained and you can see it didn’t burn all of them off, there are some left so basically his fire skimmed across the surface without creating too much heat and leaves enough litter for the next fire.
Now we can also see the young Loblollys that are coming in, a lot of these have pretty well been scorched from the ground up. A lot of these will die as well as the Yaupon, over here is a thicket of Yaupon, you can see the needles still on the branches, it was basically scorched but it was probably top kill at the base, the fire didn’t necessarily catch the bushes on fire but it girdled them at the base and these will be top kill and those stems are pretty much dead. However they will re-sprout so he will have to come back in in the next one or two years to get another fire in here to keep knocking that Yaupon back.
This prescribed burn was conducted under the ideal conditions for what was required here. The burn was conducted under relatively cool weather, light winds and relatively high humidity so the fire intensity didn’t get too high and the flame wings were fairly low, so although the heat scorched the needles, the flames were probably one to two feet as we can see from the char on the bark of these young trees here. Now the bigger trees got more scorch on them, char on the bark because there was a lot more needles right under them so the flames may have got a little bit higher on the bigger Longleafs but for the most part it was relatively mild.